Based On H. Study On The Application And Implementation Of VOIP Communication System 323

Nowadays, with the opening of the global market and the ever-increasing competition, telecommunications industry is about to witness great changes: challenges for the traditional telecommunications networks technology and the competition in the market. Voice network based on circuit switching will gradually give way to a new network based on packet switching and data communication in which IP will take the lead. Therefore; VOIP technology has become one of the many concentrations and many manufacturers are launching VOIP service one after another. The growth of VOIP technology and its service has brought great impact on the traditional telephone service especially on inland and international long distance call service, and attracted a growing number of manufacturers and device providers to be part of the VOIP field due to its enormous potentials.This paper discusses the experimental design and its realization of a communication system based on VOIP. The system is based on the project of IP telephone system of Tian Jin Education Committee. In this system, USB is conveniently used to connect PC and user telephone rather than earphone and microphone .A self-designed user terminal guarantees the USB-based communication by having a Cygnal 51 MCU and AMBE algorithm used on the terminal circuit board. The client software on the PC runs with background mode which transmits data during network with H.323 protocols. The design of the server software improves the stability and the safety of the system and provides the database of managing function for advanced users.There is no need to lay telephone line and buy telephone communication devices to build such a system. Therefore it can save all the costs for devices, lines and engineering. What is more, it is convenient to add new users and to expand the range of end users. Such a system will see a wide application in education, banking system and public security system.